Abstract:With the full consideration of the heterogeneity,existing joints,and cracks in the rock,a numerical approach of rock failure process analysis(RFPA) to simulate the stratum movement,layer separation,the whole collapse progresses,and gas permeability changing of the protected coalseam induced by deeper excavation is proposed. The numerical simulation results well displayed the whole processes of the growth of the joint,crack of the stratum and the bending,displacement,and the change of gas permeability for the protected coalseam during the deeper coalseam excavation. It also disclosed the three phases of the stratum movement,i.e.,collapse area,rupture area,and whole sunk area. It can be seen from the distribution of acoustic emission in the space that the stratum failure is transferred from deeper to surface. By the analysis of the stress fields changing,the reasons of the gas permeability improvement of the protected coalseam are presented.